+1 on the Stone Age cabs. I have a 2 x 12C with Celestion Heritage 65's and it is the best cab I have ever owned. Sensational tone and very sturdy. They are expensive but worth every penny. I have done side by side comparisons with the Bogner, Avatar, Mojotone, Marshall, Splawn and EVH and my Stone Age sounded better than them all, with the Bogner comming in a close second.

There is no "best", it is all dependant on personal taste. However, there are lots of good cabs out there. Some have been mentioned. Also, the THD, Dr.Z, Orange & Marshall 2061CX cabs are all excellent, amongst others.

Speakers are even more personal-preference dependant, and it depends completely what tones you are looking for. If you are not familiar with various flavours of speakers, then have a chat with Jim from Southbay Ampworks. He will be able to find out which speaker will suit the tones you like, the best. His Scumback speakers also have rave reviews. I have some on order, so cannot comment on any direct experience. But I was impressed enough to spend a fair amount of cash on importing some to the UK.
There are also superb Celestion, Eminence, Weber, Jensen, Tone tubby etc etc speakers. You just need to find the right ones for YOU. Unfortunately that can take a little bit of research and trial and error. Good luck !